If sticking with an exercise habit is a challenge for you, there may be an app for that. According to a University of Pennsylvania test, smartphone games help people become more active in taking exercise.

In the test, players were divided into three groups. Each group was asked to take part in one of three versions(版本)of an exercise game that recorded how many steps they took each week. The first version placed the players in competition with others. In the second version, the players worked as a group to get points. In the third, the players won points on their own, but they had to invite a friend or family member to be their supporter(支持者). This person received an e-mail each week reporting on the player’s score in the game in order to help cheer him or her on.

On the whole, all three groups had more steps than usual. And it is interesting to find that certain versions of the game worked better for people with different personalities(个性). For example, players who were more active and confident to go after their dreams would probably collect more steps by playing the competitive (the first) version. Compared with these active players, the shy or quiet players did well in all three versions, whether it was competitive, collaborative or supportive. However. those who did not pay much attention to their health and safety were not helped by the game at all.

Not all of us can get help, but exercise games do work—and work especially well what you keep your personality in mind as you choose from so many apps.

Face masks are necessary in our daily life now. But do you really know about them?

The earliest recorded face mask-like objects were in the 6th century B. C. Some drawings of people wearing a piece of cloth over their mouths were found in Persian (波斯人的) tombs.

In China, face mask-like objects first appeared during the Yuan Dynasty. The king’s servants (仆人) were asked to wear masks whenever they served food. It was believed that the masks would keep the servants’ breath from affecting (影响) the food’s smell.

In the 14th century, a serious disease called the Black Death spread to Europe. This encouraged the invention (发明) of more protective (防护的) masks. French doctor Charles de Lorme invented the beak (鸟喙) mask, which looked like the head of a bird. It completely covered the wearer’s face. The wearer had to see through the glass in the mask. The medicine in the beak section protected the wearer from diseases.

In 1910, a serious disease spread in northwestern China. The Chinese government asked Wu Liande, a medical scientist, to investigate (调查) it. Wu discovered that the disease could quickly spread through people’s breath. He invented “Wu’s mask” and advised people to wear it. Within four months, the disease was under control. Since it was cheap and easy to make, the mask was used by many people and it was the masks we use today.

Over the past years, some scientists have tried to further improve the face mask. Today, face masks are among the world’s best-selling items. They play an important role in our daily life.

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It seems that technology (技术) is everywhere. Computers and smart phones are at the center of almost everything we do. They constantly (持续地) require (需要) our attention: We text (发短信) our friends with them during the day, sleep with them by our beds and check our messages as soon as we wake up.

In the future, technology will no longer be troubling us all the time. Instead, we will use calm (平静) technology which was first developed by scientist Mark Weiser in the 1970s. In his opinion, calm technology works quietly but constantly. We know it is there, but we don’t pay much attention to it. According to Mark, the best technology should be invisible (隐形的) and let you live your life.

We already use many different types of calm technology in our everyday lives. Do you have a smoke alarm (警报器) in your house? That smoke alarm is always there, checking the air for smoke and quietly keeping you safe. It only reminds (提醒) you it’s there when you’ve burnt your bread! Or there may be lights in your home or school. When somebody passes in front of their sensors (传感器), the lights turn on. You don’t think about this type of technology until you see the light go on.

In the future, we can imagine our houses will use calm technology to open the curtains for us in the morning, to turn down the heat when we leave, or even to choose the best music for our mood (情绪). The minute we walk through the door, our house will respond (响应) by turning on the lights and music, and perhaps even starting to prepare our dinner!